Experiment name: Sunshine duration calculator
Theory: A sunshine recorder is a device that records the amount of sunshine at a given location. It measures the duration of bright sunshine and calculates the total hour of solar irradiance in a day. This data is collected over a period of time and averaged to get an idea of total solar irradiance in a given season and get the meteorological idea about the location. Cambel-Stockes sun-shine recorder is an ideal instrument that is generally used to perform this task. Although this process is done manually, but the result driven from this experiment is accurate enough to use as valid data. Cambel-Stockes sun-shine recorder is robust in nature and can be used in any geographical place for calculating sun-shine duration. Because it’s a manual process, it doesn’t need the use of electricity and thus adds to the robust nature. It consists of a spherical lense that is supported by heavy metal arrangements. This spherical shaped lense is actually the main part of the recorder and recording card (a chemically treated piece of paper) is slipped under the sphere to record the sun-shine duration data. This device should be placed in an open place where latitude will be set by moving the bowl until it is correctly placed in the correct latitude. Longitude is fixed by placing the device in the north south direction as accurately as possible with the help of a compass. A recording card is inserted to give a trial run and checked whether the burning is accurately parallel to the center line of the recording card. If not then the device should be adjusted appropriately. The cards should be changed each day after sun-set. When the card is placed in the sun-shine recorder, it must be confirmed whether the noon line of the card coincides exactly with the noon mark of the bowl. The recording cards are chemically treated so that they burn when the sunlight hits them through the spherical shaped lense.